1. Field of Invention
This invention relates to a pressure sensor that detects the presence, the absence, or the magnitude of pressure or force. More specifically, this invention relates to a pressure sensor that senses pressure or force using thin film technology.
2. Description of Related Art
Pressure sensors are typically used to detect pressure variations in a wide variety of environments, such as pressure in working devices and pressure in living environments, for example. Also, pressure sensors are used to detect pressure variations of a wide variety of mediums. For example, the pressure exerted by a fluid may be sensed. The fluid may be air or water, for example. One illustrative example of an apparatus that senses fluid pressure is a conventional air pressure gauge. Such conventional air pressure gauges commonly include a movable member that moves in proportion to an amount of air pressure exerted by an air pressure source. Also, conventional air pressure gauges commonly include a measuring or indicating member. The measuring or indicating member provides an indication of the amount of movement of the movable member. As a result, the measuring or indicating member provides an indication of the amount of pressure exerted on the movable member.
An additional illustrative example of an apparatus that senses a mechanical contact pressure is a conventional touch keyboard. Such a conventional touch keyboard is used in various devices to input information including a computer keyboard and a touch tone phone, for example. Such devices include numerous keys which must sense the application of a physical pressure. When a user exerts a physical pressure on one of the keys, an indication is generated that the user has selected that specific key.